Excellent reply.
1. I guess I can let the Hub provide Ip addresses if the Orbi controls the Wi-Fi. Cannot see any issues here.
2. If I turn off WiFi AND DHCP on the hub, how will it provide the static IP address in the hub range with a gateway address of 192.168.1.254? With DHCP off, does it not mean it cannot provide any addresses?
Exactly, that is why you have to give the Orbi a static address and gateway on the Orbi itself.
Routers, do not issue static addresses, static addresses can only be configured directly on a device. Address reservation via DHCP is often erroneously called static addressing.
Apology for asking newbie question again. I can understand giving a static address from the BT Hub range. Do I have to use the BT Hub sub address as well?
Not sure what you mean. The Orbi needs to be given a gateway address of the hub as that is where the internet will be accessed via its public IP address.
Thanks a lot guys for the help.
Couple of last questions:
1. I have a spare Asus AC86U (Router / AC mode). If it is ethernet connected to the Orbi (Orbi in Router or AC Mode), will the Asus be an Access Point (if it is placed in AP Mode)?
2. If I run Orbi in AP Mode, does the wire connection from BT hub still go to Orbi WAN port or one of the other 3 ports?
To answer both of your questions, if you connect 2 devices LAN port to LAN port, the second device will act as an access point. If you connect LAN port of the first device to WAN port of the second, bothe will be routing and natting.
As I don't have any Orbi kit, I don't know if configuring it in AP mode automatically changes the WAN port to another LAN port. However, if you connect the hub to one of the other LAN ports it won't matter either way.